We apply Bayesian Linear Regression to estimate the response rate of drivers to variable message signs at Seattle-Tacoma International Airport, or SEA. Our approach uses vehicle speed and flow data measured at the entrances of the arrival and departure-ways of the airport terminal, and sign message data. Depending on the time of day, we estimate that between 5.5 and 9.1% of drivers divert from departures to arrivals when the sign reads “departures full, use arrivals”, and conversely, between 1.9 and 4.2% of drivers divert from arrivals to departures. Though we lack counterfactual data (i.e., what would have happened had the diversionary treatment not been active), adopting a causal model that encodes time dependency with prior distributions rate can yield a measurable effect.

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The 2013 Planetary Science Decadal Survey identified a detailed investigation of the Trojan asteroids occupying Jupiter's L4 and L5 Lagrange points as a priority for future NASA missions. Observing these asteroids and measuring their physical characteristics and composition would aid in identification of their source and provide answers about their likely impact history and evolution, thus yielding information about the makeup and dynamics of the early Solar System. We present a conceptual design for a mission to the Jovian Trojan asteroids: the Trojan ASteroid Tour, Exploration, and Rendezvous (TASTER) mission, that is consistent with the NASA New Frontiers candidate mission recommended by the Decadal Survey and the final result of the 2011 NASA-JPL Planetary Science Summer School. Our proposed mission includes visits to two Trojans in the L4 population: a 500 km altitude fly-by of 1999 XS143, followed by a rendezvous with and detailed observations of 911 Agamemnon at orbital altitudes of 1000 -100 km over a 12 month nominal science data capture period. Our proposed instrument payloadwide-and narrow-angle cameras, a visual and infrared mapping spectrometer, and a neutron/gamma ray spectrometer -would provide unprecedented high-resolution, regional-toglobal datasets for the target bodies, yielding fundamental information about the early history and evolution of the Solar System. Although our mission design was completed as part of an academic exercise, this study serves as a useful starting point for future Trojan mission design studies. In particular, we identify and discuss key issues that can make large differences in the complex trade-offs required when designing a mission to the Trojan asteroids.

This paper explores the benefits and challenges of using solar energy to power unmanned aerial vehicles (UAVs) for surveillance purposes. The task of persistent surveillance requires constant supply of input energy and is of particular significance in a number of applications such as weather monitoring, wildfire control, pollution or contamination detection, target search and other long endurance missions. Here, we consider the task of monitoring a geographical area for events of varying priorities and design optimal trajectories for sufficient continuous coverage of the region and eliminate the need to devise a refueling policy. Trajectories are designed based on how the UAVs collect the solar energy to carry out the mission under a variety of dynamic and endurance constraints. An algorithm is proposed to handle the energy collection and the coverage of the target area. Different goals are set and simulation results are presented to demonstrate the ability of the UAVs to meet these goals.